| Legend |
|---|
| Justification for qualification based on EPPO PM 4 Standards |
| Justification for disqualification |
| Additional or non-conclusive information |
| Standard text |
NAME OF THE ORGANISM: Robigovirus necroavii (cherry necrotic rusty mottle virus) (CRNRM0)
GENERAL INFORMATION ON THE PEST
Name as submitted in the project specification (if different):
Cherry necrotic rusty mottle virus
Pest category:
Viruses and viroids
1- Identity of the pest/Level of taxonomic listing:
Is the organism clearly a single taxonomic entity and can it be adequately distinguished from other entities of the same rank?
Yes
Is the pest defined at the species level or lower?:
Yes
Can listing of the pest at a taxonomic level higher than species be supported by scientific reasons or can species be identified within the taxonomic rank which are the (main) pests of concern?
- Not relevant: Fruits (including hops) sector
If necessary, please list the species:
-
Is it justified that the pest is listed at a taxonomic rank below species level?
Not relevant
Conclusion:
- Candidate: Fruits (including hops) sector
Justification (if necessary):
2 – Status in the EU:
Is this pest already a quarantine pest for the whole EU?
No
Presence in the EU:
Yes
List of countries (EPPO Global Database):
Czech Republic (2020); France (2002); Greece (2008); Slovenia (2021); Spain (2017)
Conclusion:
Candidate
Justification (if necessary):
Data of the presence of this pest on the EU territory are available in EPPO Global Database (https://gd.eppo.int/).
HOST PLANT N°1: Prunus avium (PRNAV) for the Fruits (including hops) sector.
Origin of the listing:
Commission Implementing Directive (EU) 2014/98/EU and Commission Implementing Regulation (EU) 2019/2072
Plants for planting:
Plants intended for planting
3 - Is the pest already listed in a PM4 standard on the concerned host plant?
Yes
Conclusion:
Evaluation continues
Justification (if necessary):
Listed as 'Necrotic rusty mottle' in EPPO Standard PM 4-29 Certification scheme for cherry; with testing recommended. In the responses to the questionnaire, AT commented that economic impact was unclear and questioned whether it should only be regulated for pre-basic material. PL supported deregulation because mainly carried out by the vector; but AT commented that there was no known vector. Evaluation continues on these criteria.
Remark: the assessment performed covers the given host species as well as interspecific hybrids with other Prunus species.
Remark: the assessment performed covers the given host species as well as interspecific hybrids with other Prunus species.
4 - Are the listed plants for planting the main* pathway for the "pest/host/intended use" combination? (*: significant compared to others):
Yes
Conclusion:
Candidate
Justification:
The main host for cherry necrotic rusty mottle virus (CNRMV, Robigovirus necroavii) is sweet cherry (Prunus avium). However, other Prunus spp. can be infected too: sour cherry (P. cerasus), P. mahaleb, P. persica, apricot (P. armeniaca), plum (P. domestica) (Rott & Jelkmann, 2011).
In India CNRMV has been detected in what probably were naturally infected wild roses and bamboos, which grew close to CNRMV cherries (Awasthi et al., 2015a; 2015b). Its natural spread between hosts by specific Asian aphids has been proposed, but not proven (Awasthi et al. 2015c; cited in Špac et al., 2016).
CNRMV is transmitted by grafting or budding, but not mechanically with sap, and there is no known insect vector for either virus (Rott & Jelkmann 2011).
The disease is common in parts of England, where it is known as Frogmore virus canker and where it was likely introduced by infected plant material from North America (Hansen, 1995)
In India CNRMV has been detected in what probably were naturally infected wild roses and bamboos, which grew close to CNRMV cherries (Awasthi et al., 2015a; 2015b). Its natural spread between hosts by specific Asian aphids has been proposed, but not proven (Awasthi et al. 2015c; cited in Špac et al., 2016).
CNRMV is transmitted by grafting or budding, but not mechanically with sap, and there is no known insect vector for either virus (Rott & Jelkmann 2011).
The disease is common in parts of England, where it is known as Frogmore virus canker and where it was likely introduced by infected plant material from North America (Hansen, 1995)
5 - Economic impact:
Are there documented reports of any economic impact on the host?
Yes
Justification:
Symptomatic plants showed brown angular necrotic spots, the center of which can drop out giving a shot-hole appearance (Rott and Jelkmann, 2011; this article only refers to old data for economic impact). There is little recent data on the current economic significance for CNRMV. Virus-infected trees can exhibit reduced growth, significant yield losses and early death of trees (Posnette et al., 1968). Posnette and Cropley (1964) reported the disease to be widespread and prevalent in English orchards with low productivity in the ‘Frogmore’, ‘Florence’, and ‘Noble’ cultivars. In Utah it was observed that part of the buds and leaf spurs were killed, resulting in bare rangy branches that were killed in more advanced stages of the disease (Wadely, 1959) (cited in Rott & Jelkmann).
In recent studies on germplasms in Czech republic some yellowing and mottling symptoms associated with the virus were reported (Spak et al. 2017). In Slovenia, the virus was found in 4 out of 14 tested trees but no visual symptoms were recorded (Viršček Marn et al., 2021).
In recent studies on germplasms in Czech republic some yellowing and mottling symptoms associated with the virus were reported (Spak et al. 2017). In Slovenia, the virus was found in 4 out of 14 tested trees but no visual symptoms were recorded (Viršček Marn et al., 2021).
What is the likely economic impact of the pest irrespective of its infestation source in the absence of phytosanitary measures? (= official measures)
Minor
Is the economic impact due to the presence of the pest on the named host plant for planting, acceptable to the propagation and end user sectors concerned?
Yes
Is there unacceptable economic impact caused to other hosts (or the same host with a different intended use) produced at the same place of production due to the transfer of the pest from the named host plant for planting?
No
Conclusion:
Not candidate
Justification:
The literature reports about damage from times when a clear molecular or serological analysis was not possible. No recent data indicating relevant damage in the field (in orchards) were found in the literature. The recent references report about investigations in germplasm collections or random tests of asymptomatic material.
The Fruit SEWG commented that change in cultivars, rootstocks etc. may be the reason why this virus is not reported anylonger as an important problem in the recent years.
The Fruit SEWG commented that change in cultivars, rootstocks etc. may be the reason why this virus is not reported anylonger as an important problem in the recent years.
6 - Are there feasible and effective measures available to prevent the presence of the pest on the plants for planting at an incidence above a certain threshold (including zero) to avoid an unacceptable economic impact as regards the relevant host plants?
Conclusion:
Justification:
7- Is the quality of the data sufficient to recommend the pest to be listed as a RNQP?
Conclusion:
Justification:
CONCLUSION ON THE STATUS:
Disqualified: economic impact is considered acceptable in the recent years
8 - Tolerance level:
Is there a need to change the Tolerance level:
Yes
Proposed Tolerance levels:
Delisting
9 - Risk management measures:
Is there a need to change the Risk management measure:
Yes
Proposed Risk management measure:
Delisting
REFERENCES:
- Awasthi P, Ram R, Reddy SGE, Nadda G, Zaidi AA & Hallan V (2015a) Himalayan wild cherry (Prunus cerasoides) as a new natural host of Cherry necrotic rusty mottle virus (CNRMV) and a possible role of insect vectors in their transmission. Annals of Applied Biology 166, 402–409.
- Awasthi P, Ram R, Zaidi AA, Prakash O, Sood A, Hallan V (2015b) Molecular evidence for bamboo as a new
- natural host of Cherry necrotic rusty mottle virus. Forest Pathology 45, 42–50.
- Awasthi P, Dhyani D, Ram R, Zaidi AA & Hallan V (2015c). Wild roses as natural reservoirs of Cherry necrotic rusty mottle virus. European Journal of Plant Pathology 142, 403-409.
- Hansen AJ (1995) Cherry Necrotic Rusty Mottle, Lambert Mottle, and Frogmore Virus Canker. In Compendium - of Stone Fruit Diseases (eds Ogawa JM, Zehr EI, Bird GW, Ritchie DF, Uriu K & Uyemoto JK). American Phytopathological Society, St Paul, MN, USA. pages 77-75.
- Posnette AF & Cropley R (1964) Necrotic rusty mottle virus disease of sweet cherries in Britain. Plant Pathology 13, 20-22.
- Posnette AF, Cropley R & Swait AAJ (1968) Incidence of virus diseases in English sweet cherry orchards and their effect on yield. Annals of Applied Biology 61, 351-360.
- Rott M & Jelkmann W (2011) Cherry necrotic rusty mottle and cherry rusty mottle viruses. In Virus and Virus-like Diseases of Pome and Stone Fruits (eds Hadidi A, Barba M, Candresse T & Jelkmann W). American Phytopathological Society, St Paul, MN, USA. pages 133-136.
- Špak J, Přibylová J, Šafářová D, Lenz O, Koloniuk I, Navrátil M, Fránová J, Špaková V & Paprštein F (2017) Cherry necrotic rusty mottle and Cherry green ring mottle viruses in Czech cherry germplasm. Plant Protection Science 53(4), 195-200.
- Viršček Marn M., Mavrič Pleško I & Beber A (2021) First report of cherry necrotic rusty mottle virus in sweet cherries in Slovenia. J Plant Pathol 103, 1035–1036. https://doi-1org-1x7bfh51h2465.pisces.boku.ac.at/10.1007/s42161-021-00846-w.
- Wadley B (1959) Rusty mottle virus complex in Utah. Phytopathology 49, 114